KR102472171B1 - Polycyclic compound and organic electroluminescence device including the same - Google Patents

Abstract

The present invention relates to a polycyclic compound and an organic electroluminescent device including the same. A polycyclic compound according to an embodiment of the present invention is represented by Formula 1 below.
[Formula 1]

Description

Polycyclic compounds and organic electroluminescent devices containing them {POLYCYCLIC COMPOUND AND ORGANIC ELECTROLUMINESCENCE DEVICE INCLUDING THE SAME}

The present invention relates to a polycyclic compound and an organic electroluminescent device including the same.

As an image display device, organic electroluminescence displays are being actively developed. An organic electroluminescent display device is different from a liquid crystal display device and the like, and realizes display by recombination of holes and electrons injected from the first electrode and the second electrode in the light emitting layer so that a light emitting material, which is an organic compound included in the light emitting layer, emits light. It is a light emitting display device.

Examples of the organic electroluminescent element include a first electrode, a hole transport layer disposed on the first electrode, a light emitting layer disposed on the hole transport layer, an electron transport layer disposed on the light emitting layer, and a second electrode disposed on the electron transport layer. Organized organic elements are known. Holes are injected from the first electrode, and the injected holes move through the hole transport layer and are injected into the light emitting layer. Meanwhile, electrons are injected from the second electrode, and the injected electrons move through the electron transport layer and are injected into the light emitting layer. When holes and electrons injected into the light emitting layer recombine, excitons are generated in the light emitting layer. An organic electroluminescent device emits light using light generated when its excitons fall back to the ground state. In addition, the organic electroluminescent element is not limited to the structure described above, and various changes are possible. In applying the organic light emitting device to a display device, a low driving voltage and a long lifespan of the organic light emitting device are required.

An object of the present invention is to provide a polycyclic compound that can be used in an organic electroluminescent device having high luminous efficiency.

Another object of the present invention is to provide an organic electroluminescent device with high luminous efficiency and long lifetime.

A polycyclic compound according to an embodiment of the present invention is represented by Formula 1 below.

[Formula 1]

In Formula 1, X ₁ is a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms, and Ar ₁ and Ar ₂ are each It is independently a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms, or may be bonded to an adjacent group to form a ring, and R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted carbonyl group, An unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, a substituted or unsubstituted sulfinyl group, Substituted or unsubstituted sulfonyl group, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 carbon atoms for ring formation, or substituted or unsubstituted 2 to 30 carbon atoms for ring formation It is a heteroaryl group of, or may be combined with an adjacent group to form a ring, and n ₁ and n ₂ are each independently an integer of 0 or more and 4 or less. At least one of Ar ₁ , Ar ₂ , R ₁ , R ₂ and X ₁ is represented by one of Formulas 2-1 to 2-8 below.

[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

[Formula 2-4]

[Formula 2-5]

[Formula 2-6]

[Formula 2-7]

[Formula 2-8]

In Formulas 2-1 to 2-8, Y ₁ and Y ₂ are each independently N or CR ₄ , at least one of Y ₁ and Y ₂ is N, Z ₁ is O, S or NAr ₁₀ , and W ₁ to W ₅ are each independently N or CR ₅ , at least one of W ₁ to W ₅ is N, and L ₁ to L ₈ are each independently a direct linkage, substituted or unsubstituted ring carbon number 6 or more and 30 or less arylene group, or a substituted or unsubstituted heteroarylene group having 2 or more and 30 or less ring carbon atoms, and Ar ₃ to Ar ₁₀ are each independently a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, A substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for ring formation, or a substituted or unsubstituted aryl group with 2 to 30 carbon atoms for ring formation The following heteroaryl groups, or Ar ₃ to Ar ₉ may each independently bond with adjacent groups to form a ring, and R ₃ to R ₅ are each independently a hydrogen atom, a deuterium atom, a halogen atom, substituted or unsubstituted substituted or unsubstituted boron group, substituted or unsubstituted amino group, substituted or unsubstituted cyano group, substituted or unsubstituted carbonyl group, substituted or unsubstituted nitro group, substituted or unsubstituted oxy group, substituted or unsubstituted silyl group , A substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, A substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms, or R ₃ and R ₄ are each independently bonded to adjacent groups to form a ring can form

The polycyclic compound represented by Formula 1 may be represented by Formula 3 below.

[Formula 3]

In Formula 3, X ₂ is represented by any one of Formulas 2-1 to 2-8, and Ar ₁₁ and Ar ₁₂ are each independently a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted Or an unsubstituted heteroaryl group having 2 or more and 30 or more carbon atoms for forming a ring, or may be combined with an adjacent group to form a ring, and R ₆ and R ₇ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted A substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. , A substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms, or may be bonded to an adjacent group to form a ring, n ₃ and n ₄ are each independently an integer of 0 or more and 4 or less.

L ₁ to L ₈ may be a substituted or unsubstituted phenylene group. The polycyclic compound represented by Chemical Formula 3 may be represented by Chemical Formula 4 below.

[Formula 4]

In Formula 4, n ₅ is an integer of 1 to 4. When n ₅ is 1, X ₃ is a cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted sulfonyl group, or a substituted or unsubstituted A phosphine oxide group or a phenyl group substituted with a substituent represented by Formula 5-1 or 5-2 below. When n ₅ is an integer of 2 to 4, X ₃ is a cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted boron group, or a substituted or unsubstituted sulfonyl group. It is an unsubstituted phosphine oxide group or a phenylene group substituted with a substituent represented by Formula 5-1 or 5-2 below. Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined above.

[Formula 5-1]

[Formula 5-2]

In Chemical Formulas 5-1 and 5-2,

Y ₃ and Y ₄ are each independently N or CR ₉ , at least one of Y ₃ and Y ₄ is N,

Z ₂ is O, S or NAr ₁₃ ;

W ₆ to W ₁₀ are each independently N or CR ₁₀ , and at least one of W ₆ to W ₁₀ is N;

Ar ₁₃ is a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms;

R ₈ to R ₁₀ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring The following heteroaryl groups, or R ₈ and R ₉ may be independently bonded to adjacent groups to form a ring.

The polycyclic compound represented by Formula 3 may be represented by Formula 6 below.

[Formula 6]

In Formula 6, L ₉ is a substituted or unsubstituted divalent carbonyl group, a substituted or unsubstituted divalent boron group, a substituted or unsubstituted divalent sulfinyl group, a substituted or unsubstituted divalent sulfonyl group, a substituted or unsubstituted divalent sulfonyl group, An unsubstituted divalent phosphine oxide group, a substituted or unsubstituted unsubstituted pyridylene group, a substituted or unsubstituted divalent diazinyl group (diazinyl), or a substituted or unsubstituted divalent triazinyl group (triazinyl) Or, represented by Formula 7-1 or 7-2, Ar ₁₄ and Ar ₁₅ are each independently a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted ring carbon number 2 It is a heteroaryl group of 30 or more, or may be combined with adjacent groups to form a ring, and R ₁₁ to R ₁₄ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted A substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phospho group Pin oxide group, substituted or unsubstituted phosphine sulfide group, substituted or unsubstituted sulfinyl group, substituted or unsubstituted sulfonyl group, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted ring forming group An aryl group having 6 or more and 30 or less carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less carbon atoms for forming a ring, or may be bonded to an adjacent group to form a ring, and n ₆ to n ₉ are each independently 0 is an integer from 4 to 4. Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined above.

[Formula 7-1]

[Formula 7-2]

In Formulas 7-1 and 7-2, Y ₅ and Y ₆ are each independently N or CR ₁₅ , at least one of Y ₅ and Y ₆ is N, and Z ₃ and Z ₄ are each independently O, S or NAr ₁₆ , R ₁₅ is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted carbonyl group, An unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, a substituted or unsubstituted sulfinyl group, Substituted or unsubstituted sulfonyl group, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 carbon atoms for ring formation, or substituted or unsubstituted 2 to 30 carbon atoms for ring formation A heteroaryl group of, or may be combined with an adjacent group to form a ring, Ar ₁₆ is a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted ring carbon number of 2 or more and 30 or less It is a heteroaryl group of

The X ₁ may be represented by any one of Chemical Formulas 2-2-1 to 2-2-6.

[Formula 2-2-1]

[Formula 2-2-2]

[Formula 2-2-3]

[Formula 2-2-4]

[Formula 2-2-5]

[Formula 2-2-6]

In Chemical Formulas 2-2-1 to 2-2-6, L ₂ , R ₃ , R ₄ , and Ar ₁₀ are the same as defined above.

The X ₁ may be represented by any one of Chemical Formulas 2-3-1 to 2-3-3.

[Formula 2-3-1]

[Formula 2-3-2]

[Formula 2-3-3]

In Chemical Formulas 2-3-1 to 2-3-3, n ₁₀ is an integer of 0 to 4, n ₁₁ is an integer of 0 to 3, and n ₁₂ is an integer of 0 to 2. L ₃ , and R ₅ are the same as defined above.

The R ₁ and R ₂ may each independently be a hydrogen atom, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group.

An organic electroluminescent device according to an embodiment of the present invention includes a first electrode, a hole transport region disposed on the first electrode, a light emitting layer disposed on the hole transport region, an electron transport region disposed on the light emitting layer, the and a second electrode disposed on the electron transport region. The light emitting layer includes a polycyclic compound represented by Formula 1 above.
The first electrode and the second electrode are each independently Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF/Ca, LiF/Al, Mo, It may include any one selected from the group consisting of Ti, In, Zn, and Sn, two or more compounds selected from these, a mixture of two or more selected from these, or one or more oxides selected from these.

The emission layer may include a host and a dopant, and the dopant may include a polycyclic compound represented by Chemical Formula 1.

In the polycyclic compound represented by Chemical Formula 1, an energy difference (ΔE _ST ) between the lowest singlet energy level (S ₁ ) and the lowest triplet energy level (T ₁ ) may be 0.2 eV or less.

A polycyclic compound according to an embodiment of the present invention may be used as a material for an organic electroluminescent device.

An organic electroluminescent device including a polycyclic compound according to an embodiment of the present invention can implement high luminous efficiency and long lifespan.

1 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.
2 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.
3 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.

The above objects, other objects, features and advantages of the present invention will be easily understood through the accompanying drawings and the following preferred embodiments. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

Like reference numerals have been used for like elements throughout the description of each figure. In the accompanying drawings, the dimensions of the structures are shown enlarged than actual for clarity of the present invention. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise.

In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. In addition, when a part such as a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where another part is present in the middle. Conversely, when a part such as a layer, film, region, plate, etc. is said to be "under" another part, this includes not only the case where it is "directly below" the other part, but also the case where another part is in the middle.

는 연결되는 부위를 의미한다.In this specification,

indicates the connecting part.

As used herein, “substituted or unsubstituted” means a deuterium atom, a halogen group, a cyano group, a nitro group, an amino group, a silyl group, an oxy group, a thio group, a sulfinyl group, a sulfonyl group, a carbonyl group, a boron group, an aryl amine group , It may mean substituted or unsubstituted with one or more substituents selected from the group consisting of a phosphine oxide group, a phosphine sulfide group, an alkyl group, an alkenyl group, an aryl group, and a heterocyclic group. In addition, each of the substituents exemplified above may be substituted or unsubstituted. For example, a biphenyl group may be interpreted as an aryl group or a phenyl group substituted with a phenyl group.

In the present specification, “forming a ring by combining with adjacent groups” may mean forming a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocycle by combining with adjacent groups. Hydrocarbon rings include aliphatic hydrocarbon rings and aromatic hydrocarbon rings. Heterocycles include aliphatic heterocycles and aromatic heterocycles. Hydrocarbon rings and heterocycles may be monocyclic or polycyclic. In addition, rings formed by combining with each other may be connected to other rings to form a spiro structure.

In this specification, "adjacent group" may refer to a substituent substituted on an atom directly connected to the atom on which the corresponding substituent is substituted, another substituent substituted on the atom on which the corresponding substituent is substituted, or a substituent sterically closest to the corresponding substituent. have. For example, two methyl groups in 1,2-dimethylbenzene can be interpreted as "adjacent groups" to each other, and 2 methyl groups in 1,1-diethylcyclopentene The two ethyl groups can be interpreted as "adjacent groups" to each other.

In this specification, direct linkage may mean a single linkage.

In this specification, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

In this specification, the alkyl group may be straight chain, branched chain or cyclic. The number of carbon atoms of the alkyl group is 1 or more and 30 or less, 1 or more and 20 or less, 1 or more and 15 or less, 1 or more and 10 or less, or 1 or more and 6 or less. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, t-butyl group, i-butyl group, 2-ethylbutyl group, 3,3-dimethylbutyl group , n-pentyl group, i-pentyl group, neopentyl group, t-pentyl group, cyclopentyl group, 1-methylpentyl group, 3-methylpentyl group, 2-ethylpentyl group, 4-methyl-2-pentyl group , n-hexyl group, 1-methylhexyl group, 2-ethylhexyl group, 2-butylhexyl group, cyclohexyl group, 4-methylcyclohexyl group, 4-t-butylcyclohexyl group, n-heptyl group, 1 -Methylheptyl group, 2,2-dimethylheptyl group, 2-ethylheptyl group, 2-butylheptyl group, n-octyl group, t-octyl group, 2-ethyloctyl group, 2-butyloctyl group, 2-hexyl Siloctyl group, 3,7-dimethyloctyl group, cyclooctyl group, n-nonyl group, n-decyl group, adamantyl group, 2-ethyldecyl group, 2-butyldecyl group, 2-hexyldecyl group, 2-ox Tyldecyl group, n-undecyl group, n-dodecyl group, 2-ethyldodecyl group, 2-butyldodecyl group, 2-hexyldodecyl group, 2-octyldodecyl group, n-tridecyl group, n-tetradecyl group, n -Pentadecyl group, n-hexadecyl group, 2-ethylhexadecyl group, 2-butylhexadecyl group, 2-hexylhexadecyl group, 2-octylhexadecyl group, n-heptadecyl group, n-octadecyl group , n- nonadecyl group, n- icosyl group, 2-ethyl icosyl group, 2-butyl icosyl group, 2-hexyl icosyl group, 2-octyl icosyl group, n-henicosyl group, n- docosyl group, n-tricot practical group, n-tetracosyl group, n-pentacosyl group, n-hexacosyl group, n-heptacosyl group, n-octacosyl group, n-nonacosyl group, and n-triacontyl group; not limited to these

In this specification, an aryl group means any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group may be a monocyclic aryl group or a polycyclic aryl group. The number of ring carbon atoms in the aryl group may be 6 or more and 30 or less, 6 or more and 20 or less, or 6 or more and 15 or less. Examples of the aryl group include a phenyl group, a naphthyl group, a fluorenyl group, anthracenyl group, a phenanthryl group, a biphenyl group, a terphenyl group, a quaterphenyl group, a quinquephenyl group, a sexyphenyl group, a triphenylene group, a pyrenyl group, a benzo fluoranthenyl group, Although a chrysenyl group etc. can be illustrated, it is not limited to these.

In the present specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. For example, the fluorenyl group may be a 9,9'-spirobifluorenyl group.

In the present specification, the heteroaryl group may be a heteroaryl group containing at least one of O, N, P, S, Si, and Ge as heterogeneous elements. The heteroaryl group may be a monocyclic heteroaryl group or a polycyclic heteroaryl group. The number of ring carbon atoms in the heteroaryl group is 2 or more and 30 or less, or 2 or more and 20 or less. Examples of the heteroaryl group include a thiophenyl group, a furanyl group, a pyrrolyl group, an imidazolyl group, a thiazolyl group, an oxazolyl group, an oxadiazolyl group, a triazolyl group, a pyridyl group, a bipyridyl group, a pyrimidyl group, and a triazinyl group. , triazolyl group, acridyl group, pyridazinyl group, pyrazinyl group, quinolinyl group, quinazolinyl group, quinoxalinyl group, phenoxazyl group, phthalazinyl group, pyridopyrimidyl group, pyridopyrazinyl group , Pyrazino pyrazinyl group, isoquinolinyl group, indolyl group, carbazolyl group, N-arylcarbazolyl group, N-heteroarylcarbazolyl group, N-alkylcarbazolyl group, benzoxazolyl group, benzoimidazolyl group , Benzothiazolyl group, benzocarbazolyl group, benzothiophenyl group, dibenzothiophenyl group, thienothiophenyl group, benzofuranyl group, phenanthroline group (phenanthroline), thiazolyl group, isoxazolyl group, oxadiazolyl group , a thiadiazolyl group, a benzothiazolyl group, a phenothiazinyl group, a dibenzosilolyl group, and a dibenzofuranyl group, but are not limited thereto.

In this specification, the description of the aryl group described above may be applied except that the arylene group is a divalent group. The description of the heteroaryl group described above can be applied except that the heteroarylene group is a divalent group.

In this specification, the silyl group includes an alkyl silyl group and an aryl silyl group. Examples of the silyl group include a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, and a phenylsilyl group. Not limited.

In the present specification, the number of carbon atoms of the amino group is not particularly limited, but may be 1 or more and 30 or less. Amino groups can include alkyl amino groups and aryl amino groups. Examples of the amino group include, but are not limited to, a methylamino group, a dimethylamino group, a phenylamino group, a diphenylamino group, a naphthylamino group, a 9-methyl-anthracenylamino group, and a triphenylamino group.

In the present specification, the carbon number of the carbonyl group is not particularly limited, but may be 1 to 40 or less, 1 to 30 or less, or 1 to 20 or less. For example, it may have the following structure, but is not limited thereto.

In the present specification, the number of carbon atoms of the sulfonyl group and the sulfonyl group is not particularly limited, but may be 1 or more and 30 or less. Sulfinyl groups may include alkyl sulfinyl groups and aryl sulfinyl groups. Sulfonyl groups may include alkyl sulfonyl groups and aryl sulfonyl groups.

In the present specification, the thio group may include an alkyl thio group and an aryl thio group.

In this specification, the oxy group may include an alkoxy group and an aryl oxy group. An alkoxy group can be straight chain, branched chain or cyclic chain. The number of carbon atoms in the alkoxy group is not particularly limited, but may be, for example, 1 or more and 20 or less, or 1 or more and 10 or less. Examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, octyloxy, nonyloxy, decyloxy, benzyloxy, etc., but are limited to these It is not.

In this specification, the boron group includes an alkyl boron group and an aryl boron group. Examples of the boron group include, but are not limited to, trimethylboron, triethylboron, t-butyldimethylboron, triphenylboron, diphenylboron, and phenylboron.

In this specification, an alkenyl group may be straight-chain or branched-chain. The carbon number is not particularly limited, but is 2 or more and 30 or less, 2 or more and 20 or less, or 2 or more and 10 or less. Examples of the alkenyl group include, but are not limited to, a vinyl group, a 1-butenyl group, a 1-pentenyl group, a 1,3-butadienyl aryl group, a styrenyl group, and a styrylvinyl group.

In the present specification, the number of carbon atoms of the amine group is not particularly limited, but may be 1 or more and 30 or less. Amine groups may include alkyl amine groups and aryl amine groups. Examples of the amine group include, but are not limited to, a methylamine group, a dimethylamine group, a phenylamine group, a diphenylamine group, a naphthylamine group, a 9-methyl-anthracenylamine group, and a triphenylamine group.

In the present specification, among the alkylthio group, the alkylsulfoxy group, the alkylaryl group, the alkylamino group, the alkyl boron group, the alkylsilyl group, and the alkylamine group, the alkyl group is the same as the above-mentioned alkyl group.

In the present specification, an aryl group among an aryloxy group, an arylthio group, an arylsulfoxy group, an arylamino group, an aryl boron group, an arylsilyl group, and an arylamine group is the same as the aryl group described above.

Hereinafter, a polycyclic compound according to an embodiment of the present invention will be described.

A polycyclic compound according to an embodiment of the present invention is represented by Formula 1 below.

[Formula 1]

In Formula 1, X ₁ is a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms. X ₁ may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted pyrimidyl group, or a substituted or unsubstituted triazinyl group.

Ar ₁ and Ar ₂ are each independently a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms. Ar ₁ and Ar ₂ may each independently be a substituted or unsubstituted phenyl group or a substituted or unsubstituted pyrimidyl group. Alternatively, Ar ₁ and Ar ₂ may be independently bonded to adjacent groups to form a ring. Ar ₁ and Ar ₂ may combine with each other to form a ring.

R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group. Alternatively, R ₁ and R ₂ may be independently bonded to adjacent groups to form a ring. R ₁ and R ₂ may each independently be a hydrogen atom, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group.

n ₁ and n ₂ are each independently an integer of 0 or more and 4 or less. When n ₁ is 0, the polycyclic compound represented by Formula 1 may mean that it is not substituted with R ₁ . When n ₁ is an integer of 2 or greater, a plurality of R ₁ may be identical to or different from each other. When n ₂ is 0, the polycyclic compound represented by Formula 1 may mean that it is not substituted with R ₂ . When n ₂ is an integer of 2 or greater, a plurality of R ₂ may be identical to or different from each other.

In Chemical Formula 1, at least one of Ar ₁ , Ar ₂ , R ₁ , R ₂ and X ₁ is an electron acceptor or a substituent in which the electron acceptor is substituted. More specifically, at least one of Ar ₁ , Ar ₂ , R ₁ , R ₂ and X ₁ is represented by one of Formulas 2-1 to 2-8 below.

[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

[Formula 2-4]

[Formula 2-5]

[Formula 2-6]

[Formula 2-7]

[Formula 2-8]

In Formulas 2-1 to 2-8, Y ₁ and Y ₂ are each independently N or CR ₄ . At least one of Y ₁ and Y ₂ is N. Z ₁ is O, S or NAr ₁₀ . When both Y ₁ and Y ₂ are N and Z ₁ is O, the substituent represented by Chemical Formula 2-2 may be an oxadiazole derivative. When Y ₁ and Y ₂ are both N and Z ₁ is S, the substituent represented by Chemical Formula 2-2 may be a thiadiazole derivative. When both Y ₁ and Y ₂ are N and Z ₁ is NAr ₁₀ , the substituent represented by Chemical Formula 2-2 may be a triazole derivative. When any one of Y ₁ and Y ₂ is CR ₄ and Z ₁ is O, the substituent represented by Chemical Formula 2-2 may be an oxazole derivative. When any one of Y ₁ and Y ₂ is CR ₄ and Z ₁ is S, the substituent represented by Chemical Formula 2-2 may be a thiazole derivative. When any one of Y ₁ and Y ₂ is CR ₄ and Z ₁ is NAr ₁₀ , the substituent represented by Chemical Formula 2-2 may be an imidazole derivative.

W ₁ to W ₅ are each independently N or CR ₅ . At least one of W ₁ to W ₅ is N. For example, one of W ₁ to W ₅ may be N, and in this case, the substituent represented by Chemical Formula 2-3 may be a substituted or unsubstituted pyridyl group. Alternatively, two of W ₁ to W ₅ are N, and in this case, the substituent represented by Chemical Formula 2-3 may be a substituted or unsubstituted diazinyl group. Here, the diazinyl group may be a pyridazinyl group, a pyrimidyl group, or a pyrazinyl group. Alternatively, three of W ₁ to W ₅ are N, and in this case, the substituent represented by Chemical Formula 2-3 may be a substituted or unsubstituted triazinyl group. The substituent represented by Chemical Formula 2-3 may be a substituted or unsubstituted 1,3,5-triazinyl group.

L ₁ to L ₈ are each independently a direct linkage, a substituted or unsubstituted arylene group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 or more and 30 or less ring carbon atoms. . L ₁ to L ₈ may each independently be a direct linkage or a substituted or unsubstituted phenylene group.

Ar ₃ to Ar ₁₀ are each independently a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted An aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms. Ar ₃ to Ar ₁₀ may each independently be a substituted or unsubstituted phenylene group. Ar ₃ to Ar ₉ may be independently bonded to adjacent groups to form a ring.

R ₃ to R ₅ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group. R ₃ to R ₅ may each independently be a hydrogen atom, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group. R ₃ and R ₄ may each independently bond to adjacent groups to form a ring.

The substituent represented by Chemical Formula 2-2 may be represented by any one of Chemical Formulas 2-2-1 to 2-2-6.

[Formula 2-2-1]

[Formula 2-2-2]

[Formula 2-2-3]

[Formula 2-2-4]

[Formula 2-2-5]

[Formula 2-2-6]

In Chemical Formulas 2-2-1 to 2-2-6, L ₂ , R ₃ , R ₄ , and Ar ₁₀ are the same as defined above.

Substituents represented by Chemical Formula 2-3 may be represented by Chemical Formulas 2-3-1 to 2-3-3 below.

[Formula 2-3-1]

[Formula 2-3-2]

[Formula 2-3-3]

In Chemical Formulas 2-3-1 to 2-3-3, L ₃ and R ₅ are the same as defined above.

n ₁₀ may be an integer from 0 to 4. n ₁₁ may be an integer from 0 to 3. n ₁₂ may be an integer from 0 to 2. When n ₁₀ is 0, the substituent represented by Formula 2-3 may mean that it is not substituted with R ₅ . When n ₁₀ is an integer of 2 or greater, a plurality of R ₅ may be identical to or different from each other. When n ₁₁ is 0, the substituent represented by Formula 2-3 may mean that it is not substituted with R ₅ . When n ₁₁ is an integer of 2 or greater, a plurality of R ₅ may be identical to or different from each other. When n ₁₂ is 0, the substituent represented by Formula 2-3 may mean that it is not substituted with R ₅ . When n ₁₂ is 2, a plurality of R ₅ may be identical to or different from each other.

The polycyclic compound represented by Formula 1 may be represented by Formula 3 below.

[Formula 3]

In Chemical Formula 3, X ₂ may be an electron acceptor or a substituent in which the electron acceptor is substituted. X ₂ may be represented by any one of Chemical Formulas 2-1 to 2-8.

Ar ₁₁ and Ar ₁₂ may each independently be a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms. Ar ₁₁ and Ar ₁₂ may each independently be a substituted or unsubstituted phenyl group or a substituted or unsubstituted pyrimidyl group. Alternatively, Ar ₁₁ and Ar ₁₂ may be independently bonded to adjacent groups to form a ring. Ar ₁₁ and Ar ₁₂ may combine with each other to form a ring.

R ₆ and R ₇ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It may be a heteroaryl group below. Alternatively, R ₁₁ and R ₁₂ may be independently bonded to adjacent groups to form a ring. R ₁₁ and R ₁₂ may each independently be a hydrogen atom, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group.

n ₃ and n ₄ may each independently be an integer of 0 or more and 4 or less. When n ₃ is 0, the polycyclic compound represented by Formula 3 may mean that it is not substituted with R ₆ . When n ₃ is an integer of 2 or greater, a plurality of R ₆ may be identical to or different from each other. When n ₄ is 0, the polycyclic compound represented by Formula 3 may mean one not substituted with R ₇ . When n ₄ is an integer of 2 or greater, a plurality of R ₇ may be identical to or different from each other.

The polycyclic compound represented by Formula 3 may be represented by Formula 4 below.

[Formula 4]

In Formula 4, Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined above.

In Formula 4, n ₅ is an integer of 1 to 4. When n ₅ is 1, the polycyclic compound represented by Chemical Formula 4 may have one azagermine structure as an electron donor. When n ₅ is an integer of 2 to 4, the polycyclic compound represented by Chemical Formula 4 may include a plurality of azazeramine groups, which are electron donors, in the compound.

When n ₅ is 1, X ₃ is a cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted sulfonyl group, or a substituted or unsubstituted It may be a phosphine oxide group or a phenyl group substituted with a substituent represented by Formula 5-1 or 5-2 below.

When n ₅ is an integer of 2 to 4, X ₃ is a cyano group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted boron group, or a substituted or unsubstituted sulfonyl group. It may be an unsubstituted phosphine oxide group or a phenylene group substituted with a substituent represented by Formula 5-1 or 5-2 below.

[Formula 5-1]

[Formula 5-2]

In Formula 5-1, Y ₃ and Y ₄ may each independently be N or CR ₉ . At least one of Y ₃ and Y ₄ is N. Z ₂ may be O, S or NAr ₁₃ . When both Y ₃ and Y ₄ are N and Z ₂ is O, the substituent represented by Chemical Formula 5-1 may be an oxadiazole derivative. When both Y ₃ and Y ₄ are N and Z ₂ is S, the substituent represented by Chemical Formula 5-1 may be a thiadiazole derivative. When both Y ₃ and Y ₄ are N and Z ₂ is NAr ₁₃ , the substituent represented by Chemical Formula 5-1 may be a triazole derivative. When any one of Y ₃ and Y ₄ is CR ₈ and Z ₂ is O, the substituent represented by Chemical Formula 5-1 may be an oxazole derivative. When any one of Y ₃ and Y ₄ is CR ₈ and Z ₂ is S, the substituent represented by Formula 5-1 may be a thiazole derivative. Either one of Y ₃ and Y ₄ is CR ₈ and When Z ₂ is NAr ₁₃ , the substituent represented by Chemical Formula 5-1 may be an imidazole derivative. The substituent represented by Chemical Formula 5-1 may be an azole derivative.

In Chemical Formula 5-2, W ₆ to W ₁₀ may each independently be N or CR ₁₀ . At least one of W ₆ to W ₁₀ is N. For example, one of W ₆ to W ₁₀ may be N, and in this case, the substituent represented by Chemical Formula 5-2 may be a substituted or unsubstituted pyridyl group. Alternatively, two of W ₆ to W ₁₀ are N, and in this case, the substituent represented by Chemical Formula 5-2 may be a substituted or unsubstituted diazinyl group. Here, the diazinyl group may be a pyridazinyl group, a pyrimidyl group, or a pyrazinyl group. Alternatively, three of W ₆ to W ₁₀ are N, and in this case, the substituent represented by Chemical Formula 5-2 may be a substituted or unsubstituted triazinyl group. The substituent represented by Chemical Formula 5-2 may be a substituted or unsubstituted 1,3,5-triazinyl group. The polycyclic compound represented by Formula 3 may be represented by Formula 6 below.

[Formula 6]

In Formula 6, Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined above.

In Formula 6, L ₉ may be a linker composed of an electron acceptor. L ₉ is a substituted or unsubstituted divalent carbonyl group, a substituted or unsubstituted divalent boron group, a substituted or unsubstituted divalent sulfinyl group, a substituted or unsubstituted divalent sulfonyl group, or a substituted or unsubstituted divalent sulfonyl group; It may be a phosphine oxide group, a substituted or unsubstituted unsubstituted pyridylene group, a substituted or unsubstituted divalent diazinyl group, or a substituted or unsubstituted divalent triazinyl group. Alternatively, L ₉ may be represented by Formula 7-1 or 7-2 below.

[Formula 7-1]

[Formula 7-2]

In Formula 7-1, Y ₅ and Y ₆ may each independently be N or CR ₁₅ . At least one of Y ₅ and Y ₆ is N. Z ₃ may be O, S or NAr ₁₆ . When both Y ₅ and Y ₆ are N and Z ₃ is O, the substituent represented by Chemical Formula 7-1 may be an oxadiazole derivative. When both Y ₅ and Y ₆ are N and Z ₃ is S, the substituent represented by Chemical Formula 7-1 may be a thiadiazole derivative. When both Y ₅ and Y ₆ are N and Z ₃ is NAr ₁₆ , the substituent represented by Chemical Formula 7-1 may be a triazole derivative. When any one of Y ₅ and Y ₆ is CR ₁₅ and Z ₃ is O, the substituent represented by Chemical Formula 7-1 may be an oxazole derivative. When any one of Y ₅ and Y ₆ is CR ₁₅ and Z ₃ is S, the substituent represented by Chemical Formula 7-1 may be a thiazole derivative. When any one of Y ₅ and Y ₆ is CR ₁₅ and Z ₃ is NAr ₁₆ , the substituent represented by Chemical Formula 7-1 may be an imidazole derivative.

In Formula 7-2, Z ₄ may be O, S or NAr ₁₆ .

Ar ₁₄ to Ar ₁₆ may each independently be a substituted or unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms. Ar ₁₄ to Ar ₁₆ may each independently be a substituted or unsubstituted phenyl group. Alternatively, Ar ₁₄ and Ar ₁₅ may be independently bonded to adjacent groups to form a ring. Ar ₁₄ and Ar ₁₅ may combine with each other to form a ring.

R ₁₁ to R ₁₄ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It may be a heteroaryl group below. R ₁₁ to R ₁₄ may each independently be a hydrogen atom, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group. Alternatively, R ₁₁ to R ₁₄ may be independently bonded to adjacent groups to form a ring.

The polycyclic compound represented by Formula 1 may be any one selected from compounds represented in Compound Group 1 below. However, it is not limited thereto.

[Compound group 1]

.

.

The polycyclic compound represented by Chemical Formula 1 may be any one selected from compounds represented in Compound Group 2 below. However, it is not limited thereto.

[Compound group 2]

.

.

The polycyclic compound represented by Chemical Formula 1 may be any one selected from compounds represented in Compound Group 3 below. However, it is not limited thereto.

[Compound group 3]

.

.

The polycyclic compound according to an embodiment of the present invention includes an azagermine group including heavy atom Ge as an electron donor, and includes a cyano group, a carbonyl group, a boron group, a sulfinyl group, and a sulfone group. An electron acceptor includes a yl group, a phosphine oxide group, a pyridyl group, a diazinyl group, a triazinyl group, or an azole group.

When the polycyclic compound represented by Chemical Formula 1 is applied to an organic electroluminescent device, high luminous efficiency and long lifespan can be secured. The polycyclic compound represented by Chemical Formula 1 includes an azagermine group including heavy atom Ge as an electron donor. In the polycyclic compound represented by Chemical Formula 1, due to the heavy atom included in the electron donor, spin-orbit coupling is increased, and singlet-triplet intersystem crossing may be promoted. Therefore, the polycyclic compound according to an embodiment of the present invention is used as a dopant material of the light emitting layer of an organic electroluminescent device, and can efficiently perform thermally activated delayed fluorescence (TADF) without loss of energy of triplet excitons.

Hereinafter, an organic electroluminescent device according to an embodiment of the present invention will be described. Hereinafter, differences from the polycyclic compound according to an embodiment of the present invention described above will be mainly described in detail, and parts not described depend on the polycyclic compound according to an embodiment of the present invention described above.

An organic electroluminescent device according to an embodiment of the present invention includes the above-described polycyclic compound according to an embodiment of the present invention.

1 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention. 2 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention. 3 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.

1 to 3, the organic electroluminescent device 10 according to an embodiment of the present invention includes a first electrode EL1, a hole transport region HTR, a light emitting layer EML, and an electron transport region ETR. and a second electrode EL2.

The first electrode EL1 has conductivity. The first electrode EL1 may be a pixel electrode or an anode. The first electrode EL1 may be a transmissive electrode, a transflective electrode, or a reflective electrode. When the first electrode EL1 is a transmissive electrode, the first electrode EL1 is a transparent metal oxide, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium ITZO (ITZO). tin zinc oxide) and the like. When the first electrode EL1 is a transflective electrode or a reflective electrode, the first electrode EL1 is Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF/Ca, LiF/Al, Mo, Ti, or a compound or mixture thereof (eg, a mixture of Ag and Mg). Alternatively, a plurality of layer structures including a reflective film or semi-transmissive film formed of the above material and a transparent conductive film formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), or the like. can be

The hole transport region HTR is disposed on the first electrode EL1. The hole transport region HTR may include at least one of a hole injection layer (HIL), a hole transport layer (HTL), a hole buffer layer, and an electron blocking layer.

The hole transport region HTR may have a single layer structure made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

For example, as shown in FIG. 2 , the hole transport region HTR may have a structure of a hole injection layer (HIL) or a single layer of a hole transport layer (HTL), and is composed of a hole injection material and a hole transport material. It may have a single layer structure. In addition, the hole transport region HTR has a structure of a single layer made of a plurality of different materials, or a hole injection layer HIL / hole transport layer HTL sequentially stacked from the first electrode EL1, hole injection layer (HIL) / hole transport layer (HTL) / hole buffer layer, hole injection layer (HIL) / hole buffer layer, hole transport layer (HTL) / hole buffer layer or hole injection layer (HIL) / hole transport layer (HTL) / electron blocking layer It may have a structure, but is not limited thereto.

As shown in FIG. 3 , the hole transport region HTR may have a plurality of hole transport layers. The hole transport region HTR may include a first hole transport layer HTL1 and a second hole transport layer HTL2 disposed on the first hole transport layer HTL1. The second hole transport layer HTL2 may be a hole transport layer adjacent to the light emitting layer EML among the plurality of hole transport layers.

The hole transport region (HTR) is formed by various methods such as vacuum deposition method, spin coating method, cast method, LB method (Langmuir-Blodgett), inkjet printing method, laser printing method, laser induced thermal imaging (LITI), and the like. can be formed using

The hole injection layer (HIL) may include, for example, a phthalocyanine compound such as copper phthalocyanine; DNTPD (N,N'-diphenyl-N,N'-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine), m-MTDATA (4,4' ,4"-tris(3-methylphenylphenylamino)triphenylamine), TDATA(4,4'4"-Tris(N,N-diphenylamino)triphenylamine), 2-TNATA(4,4',4"-tris{N,- (2-naphthyl)-N-phenylamino}-triphenylamine), PEDOT/PSS (Poly(3,4-ethylenedioxythiophene)/Poly(4-styrenesulfonate)), PANI/DBSA (Polyaniline/Dodecylbenzenesulfonic acid), PANI/CSA (Polyaniline /Camphor sulfonicacid), PANI/PSS((Polyaniline)/Poly(4-styrenesulfonate)), NPD(N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl) -4,4′-diamine), polyether ketone containing triphenylamine (TPAPEK), 4-Isopropyl-4’-methyldiphenyliodonium Tetrakis(pentafluorophenyl)borate], HAT-CN(1,4,5,8,9 ,11-Hexaazatriphenylenehexacarbonitrile) and the like.

The hole transport layer (HTL) is, for example, N-phenylcarbazole, polyvinylcarbazole, mCP (1,3-Bis (N-carbazolyl) benzene), carbazole-based derivatives, fluorene-based derivatives, TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine), TCTA(4,4',4"-tris(N- triphenylamine derivatives such as carbazolyl)triphenylamine), NPD (N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine), TAPC(4,4'-Cyclohexylidene bis[N,N-bis(4-methylphenyl)benzenamine]), HMTPD(4,4'-Bis[N,N'-(3-tolyl)amino]-3,3' -dimethylbiphenyl) and the like.

The hole transport region HTR may have a thickness of about 150 Å to about 12000 Å, for example, about 150 Å to about 1500 Å. If the hole transport region (HTR) includes both the hole injection layer (HIL) and the hole transport layer (HTL), the thickness of the hole injection layer (HIL) is about 100 Å to about 10000 Å, for example, about 100 Å to about 1000 Å, The hole transport layer (HTL) may have a thickness of about 50 Å to about 1000 Å. When the thicknesses of the hole transport region HTR, the hole injection layer HIL, and the hole transport layer HTL satisfy the ranges described above, satisfactory hole transport characteristics may be obtained without a substantial increase in driving voltage.

In addition to the aforementioned materials, the hole transport region HTR may further include a charge generating material to improve conductivity. The charge generating material may be uniformly or non-uniformly dispersed within the hole transport region (HTR). The charge generating material may be, for example, a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, and a compound containing a cyano group, but is not limited thereto. For example, non-limiting examples of the p-dopant include quinone derivatives such as TCNQ (Tetracyanoquinodimethane) and F4-TCNQ (2,3,5,6-tetrafluoro-tetracyanoquinodimethane), metal oxides such as tungsten oxide and molybdenum oxide, and the like. It may include, but is not limited thereto.

As described above, the hole transport region HTR may further include at least one of a hole buffer layer and an electron blocking layer in addition to the hole injection layer HIL and the hole transport layer HTL. The hole buffer layer may increase light emission efficiency by compensating for a resonance distance according to a wavelength of light emitted from the light emitting layer EML. A material that can be included in the hole transport region (HTR) may be used as a material included in the hole buffer layer. The electron blocking layer is a layer that serves to prevent injection of electrons from the electron transport region ETR to the hole transport region HTR.

The light emitting layer EML is disposed on the hole transport region HTR. The light emitting layer (EML) may be disposed on the hole transport layer (HTL) and contact the hole transport layer (HTL). The thickness of the light emitting layer EML may be, for example, about 100 Å to about 600 Å. The light emitting layer EML may have a single layer structure made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

Hereinafter, the case in which the polycyclic compound according to the embodiment of the present invention described above is included in the light emitting layer EML will be described as an example. However, it is not limited thereto, and the polycyclic compound according to an embodiment of the present invention may be included in at least one layer among one or more organic layers disposed between the first electrode EL1 and the second electrode EL2. .

The light emitting layer EML may include a polycyclic compound according to an embodiment of the present invention described above. Specifically, the organic electroluminescent device according to an embodiment of the present invention may include a polycyclic compound represented by Chemical Formula 1 in the light emitting layer (EML).

[Formula 1]

In Formula 1, X ₁ , Ar ₁ , Ar ₂ , A detailed description of R ₁ , R ₂ , n ₁ , and n ₂ is the same as described above, and thus will be omitted.

A detailed description of the polycyclic compound represented by Chemical Formula 1 will be omitted as the above description can be applied as it is.

The light emitting layer EML may emit one of red light, green light, blue light, white light, yellow light, and cyan light. The light emitting layer EML may include a fluorescent material or a phosphorescent material. A polycyclic compound according to an embodiment of the present invention may be a material for thermally activated delayed fluorescence (TADF). The polycyclic compound according to an embodiment of the present invention may be a material for thermally activated delayed fluorescence (TADF) emitting blue light. In the polycyclic compound according to an embodiment of the present invention, an energy difference (ΔE _ST ) between the lowest singlet energy level (S ₁ ) and the lowest triplet energy level (T ₁ ) may be about 0.2 eV or less.

In addition, the light emitting layer EML may include a host and a dopant.

As the host material of the light emitting layer (EML), anthracene derivatives, fluoranthene derivatives, pyrene derivatives, arylacetylene derivatives, fluorene derivatives, perylene derivatives, It is selected from chrysene derivatives, phenanthrene derivatives and the like, and preferably includes pyrene derivatives, perylene derivatives, chrysene derivatives, phenanthrene derivatives and anthracene derivatives. For example, as a host material of the light emitting layer (EML), an anthracene derivative represented by Chemical Formula 8 may be used.

[Formula 8]

In Formula 8, Y ₁ to Y ₄ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 15 carbon atoms, and a substituted or unsubstituted ring. An aryl group having 6 to 30 carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for ring formation, m ₁ and m ₂ are each independently an integer of 0 to 4, and m ₃ and m ₄ are each independently an integer of 0 or more and 5 or less. In Formula 8, Y ₃ and Y ₄ may independently bond to adjacent groups to form a ring.

Examples of the compound represented by Formula 8 include compounds represented by the following structural formula. However, the compound represented by Formula 8 is not limited to the following.

.

.

The host is not particularly limited as long as it is a commonly used material, but, for example, Alq ₃ (tris (8-hydroxyquinolino) aluminum), CBP (4,4'-bis (N-carbazolyl) -1,1'-biphenyl) , PVK(poly(N-vinylcabazole), ADN(9,10-di(naphthalene-2-yl)anthracene), TCTA(4,4',4''-Tris(carbazol-9-yl)-triphenylamine), TPBi(1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene), TBADN(3-tert-butyl-9,10-di(naphth-2-yl)anthracene), DSA(distyrylarylene), CDBP (4,4′-bis(9-carbazolyl)-2,2′-dimethyl-biphenyl), MADN (2-Methyl-9,10-bis(naphthalen-2-yl)anthracene), and the like may be included.

The polycyclic compound represented by Chemical Formula 1 may be included as a dopant material of the light emitting layer (EML). The polycyclic compound represented by Chemical Formula 1 may be a dopant material for thermally activated delayed fluorescence (TADF).

In the organic electroluminescent device according to an embodiment of the present invention, the dopant may further include a known material in addition to the polycyclic compound represented by Chemical Formula 1. The dopant is, for example, a styryl derivative (e.g., 1,4-bis[2-(3-N-ethylcarbazoryl)vinyl]benzene(BCzVB), 4-(di-p-tolylamino)-4'-[ (di-p-tolylamino)styryl]stilbene (DPAVB), N-(4-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl )-N-phenylbenzenamine (N-BDAVBi), perylene and its derivatives (eg 2,5,8,11-Tetra-tert-butylperylene (TBP)), pyrene and its derivatives (eg 1, It may include dopants such as 1-dipyrene, 1,4-dipyrenylbenzene, 1,4-Bis (N, N-Diphenylamino) pyrene), etc. The dopant is ACRSA (10-phenyl-10H,10'H-spiro[acridine -9,9'-anthracen] -10'-one).

When the light emitting layer (EML) emits red light, the light emitting layer (EML) is, for example, a fluorescent material containing PBD:Eu(DBM) ₃ (Phen) (tris(dibenzoylmethanato)phenanthoroline europium) or perylene. may further include. When the light emitting layer (EML) emits red light, the dopant included in the light emitting layer (EML) is, for example, PIQIr (acac) (bis (1-phenylisoquinoline) acetylacetonate iridium), PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium), metal complexes or organometallic complexes such as tris(1-phenylquinoline)iridium (PQIr) and octaethylporphyrin platinum (PtOEP), rubrene and its derivatives, and 4-dicyano methylene-2-(p-dimethylaminostyryl)-6-methyl-4H-pyran (DCM) and its derivatives.

When the light emitting layer EML emits green light, the light emitting layer EML may further include a fluorescent material including, for example, Alq ₃ (tris(8-hydroxyquinolino)aluminum). When the light emitting layer (EML) emits green light, the dopant included in the light emitting layer (EML) is, for example, a metal complex compound such as Ir(ppy) ₃ (fac-tris(2-phenylpyridine)iridium) or an organic material. It can be selected from organometallic complex and coumarin and its derivatives.

When the light emitting layer (EML) emits blue light, the light emitting layer (EML) is, for example, spiro-DPVBi (spiro-DPVBi), spiro-6P (spiro-6P), DSB (distyryl-benzene), DSA (distyryl- arylene), PFO (Polyfluorene) polymer, and PPV (poly (p-phenylene vinylene) polymer. When the light emitting layer (EML) emits blue light , The dopant included in the light emitting layer (EML) is selected from, for example, a metal complex such as (4,6-F2ppy) ₂ Irpic or an organometallic complex, perylene, and derivatives thereof. can

The electron transport region ETR is disposed on the light emitting layer EML. The electron transport region ETR may include at least one of a hole blocking layer, an electron transport layer ETL, and an electron injection layer EIL, but is not limited thereto.

The electron transport region ETR may have a single layer structure made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

For example, as shown in FIG. 2 , the electron transport region ETR may have a single layer structure of an electron injection layer (EIL) or an electron transport layer (ETL), and is composed of an electron injection material and an electron transport material. It may have a single layer structure. In addition, the electron transport region ETR has a structure of a single layer made of a plurality of different materials, or an electron transport layer (ETL) / electron injection layer (EIL), a hole blocking layer / It may have an electron transport layer (ETL)/electron injection layer (EIL) structure, but is not limited thereto.

As shown in FIG. 3 , the electron transport region ETR may have a plurality of electron transport layers. The electron transport region ETR may include a first electron transport layer ETL1 and a second electron transport layer ETL2 disposed on the first electron transport layer ETL1 . The first electron transport layer ETL1 may be an electron transport layer adjacent to the light emitting layer EML among the plurality of electron transport layers.

The electron transport region (ETR) is formed by various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB), inkjet printing, laser printing, and laser induced thermal imaging (LITI). can be formed using

The electron transport layer (ETL) is, for example, Alq ₃ (Tris(8-hydroxyquinolinato)aluminum), 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene, 2,4,6- tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzoimidazolyl-1-ylphenyl)-9,10-dinaphthylanthracene, TPBi 1,3,5-Tri(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl), BCP(2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphen( 4,7-Diphenyl-1,10-phenanthroline), TAZ(3-(4-Biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole), NTAZ(4-(Naphthalen-1 -yl)-3,5-diphenyl-4H-1,2,4-triazole), tBu-PBD(2-(4-Biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole ), BAlq (Bis(2-methyl-8-quinolinolato-N1,O8)-(1,1'-Biphenyl-4-olato)aluminum), Bebq ₂ (berylliumbis(benzoquinolin-10-olate), ADN(9, 10-di(naphthalene-2-yl)anthracene), bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), and mixtures thereof, but is not limited thereto. may be about 100 Å to about 1000 Å, for example, about 150 Å to about 500 A. When the thicknesses of the electron transport layers (ETLs) satisfy the aforementioned range, satisfactory electron transport characteristics can be obtained without a substantial increase in driving voltage. can

When the electron transport region ETR includes the electron injection layer EIL, metals such as Al, Ag, Li, Mg, and Ca, and mixtures thereof may be included. However, it is not limited thereto. For example, a lanthanide metal such as LiF, lithium quinolate (LiQ), Li ₂ O, BaO, NaCl, CsF, or Yb, or a metal halide such as RbCl or RbI may be used for the electron injection layer (EIL). It is not limited. The electron injection layer (EIL) may also be made of a mixture of an electron transport material and an insulating organometal salt. The organometallic salt may be a material having an energy band gap of about 4 eV or more. Specifically, for example, the organometallic salt may include metal acetate, metal benzoate, metal acetoacetate, metal acetylacetonate or metal stearate. can The electron injection layers (EILs) may have a thickness of about 10 Å to about 100 Å. When the thickness of the electron injection layers (EIL) satisfies the aforementioned range, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.

As mentioned above, the electron transport region ETR may include a hole blocking layer. The hole blocking layer may include, for example, at least one of BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) and Bphen (4,7-diphenyl-1,10-phenanthroline). However, it is not limited thereto.

The second electrode EL2 is disposed on the electron transport region ETR. The second electrode EL2 may be a common electrode or a cathode. The second electrode EL2 may be a transmissive electrode, a transflective electrode, or a reflective electrode. When the second electrode EL2 is a transmissive electrode, the second electrode EL2 is a transparent metal oxide, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium ITZO (indium tin oxide). tin zinc oxide) and the like.

When the second electrode EL2 is a transflective electrode or a reflective electrode, the second electrode EL2 is Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF/Ca, LiF/Al, Mo, Ti, or a compound or mixture thereof (eg, a mixture of Ag and Mg). Alternatively, a plurality of layer structures including a reflective film or semi-transmissive film formed of the above material and a transparent conductive film formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), or the like. can be

Although not shown, the second electrode EL2 may be connected to the auxiliary electrode. When the second electrode EL2 is connected to the auxiliary electrode, resistance of the second electrode EL2 may be reduced.

In the organic electroluminescent device 10, as voltage is applied to the first electrode EL1 and the second electrode EL2, holes injected from the first electrode EL1 form the hole transport region HTR. The electrons injected from the second electrode EL2 are transferred to the light emitting layer EML through the electron transport region ETR. Electrons and holes recombine in the light emitting layer (EML) to generate excitons, and as the excitons fall from an excited state to a ground state, they emit light.

When the organic electroluminescent device 10 is a top emission type, the first electrode EL1 may be a reflective electrode, and the second electrode EL2 may be a transmissive electrode or a transflective electrode. When the organic electroluminescent device 10 is a bottom emission type, the first electrode EL1 may be a transmissive electrode or a transflective electrode, and the second electrode EL2 may be a reflective electrode.

An organic electroluminescent device according to an embodiment of the present invention includes a polycyclic compound represented by Chemical Formula 1, and can secure high luminous efficiency and long lifespan. The polycyclic compound according to an embodiment of the present invention is used as a dopant material of the light emitting layer, so that high light emitting efficiency of the organic electroluminescent device can be realized. Specifically, the polycyclic compound represented by Chemical Formula 1 includes an azagermine group including heavy atom Ge as an electron donor, and due to the heavy atom included in the electron donor, spin-orbit interaction (Spin Orbit Coupling) is increased, and singlet-triplet intersystem crossing may be promoted. Therefore, an organic electroluminescent device using this as a dopant material can efficiently perform thermally activated delayed fluorescence (TADF) without loss of energy of triplet excitons.

Hereinafter, the present invention will be described in more detail through specific manufacturing methods, Examples and Comparative Examples. The following examples are merely examples to aid understanding of the present invention, and the scope of the present invention is not limited thereto.

A polycyclic compound according to an embodiment of the present invention may be synthesized as follows, for example. However, it is not limited thereto.

(synthesis example)

1. Synthesis of Compound 11

(Synthesis of Compound A)

Under an argon (Ar) atmosphere, 12.5 g (30.0 mmol) of Benzylbis(2-bromophenyl)amine was added to 300 mL of dehydrated THF solution in a 1000 mL three-neck flask, and the mixture was stirred at -78°C. In addition, 37.5 mL (60.0 mmol) of a 1.6 M n-BuLi solution in Hexane was added dropwise, and the mixture was stirred for 2 hours. Diphenyldichlorogerman 6.3 mL (30.0 mmol) dehydrated THF solution (30 mL) was added dropwise thereto, and after stirring at -78°C for 2 hours, the mixture was stirred at room temperature for 3 hours. After the reaction, the liquid mixture was washed with water. The obtained organic phase was concentrated to obtain a viscous substance. The obtained crude product was purified by silica gel column chromatography to obtain 9.00 g (yield: 62%) of Compound A as a white solid. The molecular weight of compound A measured by FAB-MS measurement was 485.

(Synthesis of Compound B)

Under an argon (Ar) atmosphere, 2.97 g (18.6 mmol) of Pd black and 9.00 g (18.6 mmol) of Compound A were added to 350 mL of a dehydrated dichloromethane solution in a 1000 mL three-necked flask. Here, the inside of the flask was stirred at room temperature under a hydrogen (H ₂ - ) atmosphere for 12 hours. This was washed with water, the resulting organic phase was concentrated, and the obtained crude product was purified by silica gel column chromatography to obtain 3.37 g (yield: 46%) of Compound B as a white solid. The molecular weight of compound B measured by FAB-MS measurement was 395.

(Synthesis of Compound 11)

3.16 g (8.0 mmol) of compound B, 1.56 g (4.0 mmol) of 4,6-Bis (4-bromophenyl) pyrimidine, and 0.183 g (0.20 mmol) of Pd ₂ (dba) ₃ in a 100 mL three-necked flask under an argon (Ar) atmosphere. , ( ^t Bu) 3P 0.162 g (0.80 mmol) and sodium _tert -butoxide 0.769 g (8.0 mmol) were added, and the mixture was stirred at 80°C for 12 hours in a 16 mL toluene solvent. After air cooling, water was added, the organic layer was fractionated, and the solvent was evaporated under reduced pressure. The obtained crude product was purified by silica gel column chromatography to obtain 2.35 g (yield 58%) of Compound 11 as a white solid. The molecular weight of Compound 12 measured by FAB-MS was 1018. In addition, the chemical shift values of the compounds measured in the ¹ H-NMR measurement were [9.26 (1H), 7.74-7.67 (5H), 7.38-7.28 (32H), 7.18 (4H), 7.01 (4H)] was Through the above results, it was confirmed that the compound of white solid was Compound 11.

2. Synthesis of Compound 25

Compound B was synthesized in the same manner as in the synthesis method of compound 11 described above. 3.16g (8.0 mmol) of compound B, 1.36g (4.0 mmol) of 4,4'-Dibromobenzophenone, 0.183g (0.20 mmol) of Pd ₂ (dba) ₃ , ( ^t Bu) 0.162 g (0.80 mmol) of 3P and 0.769 g (8.0 mmol) of sodium _tert -butoxide were added, and the mixture was stirred at 80°C for 12 hours in a 16 mL toluene solvent. After air cooling, water was added, the organic layer was fractionated, and the solvent was evaporated under reduced pressure. The obtained crude product was purified by silica gel column chromatography to obtain 2.01 g (yield 52%) of Compound 25 as a white solid. The molecular weight of compound 25 measured by FAB-MS was 968. In addition, the chemical shift values of the compounds measured in the ¹ H-NMR measurement were [7.71 (4H), 7.37-7.27 (32H), 7.18 (4H), 7.01 (4H)]. Through the above results, it was confirmed that the compound of the white solid was Compound 25.

3. Synthesis of Compound 39

Compound B was synthesized in the same manner as in the synthesis method of compound 11 described above. Thereafter, 3.16 g (8.0 mmol) of compound B and 3-bromo-10-[2,4,6-tris(1-methylethyl)phenyl]-10H-Phenoxaborin 3.69 were added to a 100 mL three-necked flask under an argon (Ar) atmosphere. g (8.0 mmol), Pd ₂ (dba) ₃ 0.183 g (0.20 mmol), ( ^t Bu) ₃ P 0.162 g (0.80 mmol), Sodium tert-butoxide 0.769 g (8.0 mmol) was added, in 16 mL toluene solvent It stirred at 80 degreeC for 12 hours. After air cooling, water was added, the organic layer was fractionated, and the solvent was evaporated under reduced pressure. The obtained crude product was purified by silica gel column chromatography to obtain 5.15 g (yield 83%) of Compound 39 as a white solid. The molecular weight of compound 39 measured by FAB-MS was 775. In addition, the chemical shift values of the compounds measured in ¹ H-NMR measurement were [7.72-7.66 (2H), 7.37-7.28 (17H), 7.18 (2H), 7.08-6.99 (4H), 6.91-6.85 (2H), 2.89-2.86 (3H), 1.21-1.17 (18H)]. Through the above results, it was confirmed that the compound of white solid was Compound 39.

4. Synthesis of Compound 49

Compound B was synthesized in the same manner as in the synthesis method of compound 11 described above. Thereafter, 3.16 g (8.0 mmol) of Compound B, 1.50 g (4.0 mmol) of 1,1'-Sulfonylbis[4-bromobenzene], and 0.183 g of Pd ₂ (dba) ₃ were placed in a 100 mL three-necked flask under an argon (Ar) atmosphere. (0.20 mmol), ( ^tBu ) 3P 0.162 g (0.80 mmol) and sodium _tert -butoxide 0.769 g (8.0 mmol) were added, and the mixture was stirred at 80°C for 12 hours in a 16 mL toluene solvent. After air cooling, water was added, the organic layer was fractionated, and the solvent was evaporated under reduced pressure. The obtained crude product was purified by silica gel column chromatography to obtain 1.81 g (yield 45%) of Compound 49 as a white solid. The molecular weight of compound 49 measured by FAB-MS was 1004. In addition, the chemical shift values of the compounds measured in the ¹ H-NMR measurement were [7.62 (4H), 7.37-7.28 (32H), 7.18 (4H), 7.01 (4H)]. Through the above results, it was confirmed that the compound of white solid was Compound 49.

(experimental example)

(Example of device creation)

The organic electroluminescent devices of Examples 1 to 4 were fabricated using the above-described compounds 11, 25, 39, and 49 as dopant materials for the light emitting layer.

[Example compound]

The following Comparative Example compounds c1 to c5 were used to prepare the Comparative Example device.

[Comparative Example Compound]

In the organic EL devices of Examples 1 to 4 and Comparative Examples 1 to 9, a first electrode having a thickness of 120 nm was formed of ITO, and a first electrode was formed of ITO and 10 nm thick using HAT-CN (1,4,5,8,9,11-Hexaazatriphenylenehexacarbonitrile). Forming a hole injection layer of NPD (N,N'-Di(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine) to form a 80nm thick 1 Forming a hole transport layer, forming a second hole transport layer with a thickness of 5 nm with mCP (1,3-Bis (N-carbazolyl) benzene), and forming a second hole transport layer with DPEPO (bis [2- (diphenylphosphino) phenyl] ether oxide) A 20 nm thick light emitting layer doped with a compound or a comparative compound by 20% was formed, a 10 nm thick first electron transport layer was formed with DPEPO (bis [2- (diphenylphosphino) phenyl] ether oxide), and TPBi (1,3, A 30 nm thick second electron transport layer was formed with 5-tris(N-phenylbenzimidazole-2-yl)benzene), a 0.5 nm thick electron injection layer was formed with LiF, and a 100 nm thick second electrode was formed with Al. . Each layer was formed by vapor deposition in a vacuum atmosphere.

(experimental example)

Emission wavelength, external quantum efficiency (EQE), and half-life of the organic electroluminescent devices prepared from Experimental Example Compounds 11, 25, 39, and 49 and Comparative Example Compounds c1 to c9 were evaluated. The evaluation results are shown in Table 1 below. The external quantum efficiency of each Example and Comparative Example is a measured value at a current density of 10 mA/cm ² , and the half life is measured by the luminance half-life time from the initial luminance of 100 cd/m ² .

Element creation example dopant emission wavelength
(nm) external quantum efficiency
(%) life span
LT ₅₀ (h) Example 1 Example compound 11 460 10.8 29.2 Example 2 Example compound 25 466 14.0 33.4 Example 3 Example compound 39 447 12.0 8.7 Example 4 Example compound 49 433 10.1 12.1 Comparative Example 1 Comparative Example Compound c1 500 8.0 16.0 Comparative Example 2 Comparative Example Compound c2 506 10.8 19.9 Comparative Example 3 Comparative Example Compound c3 488 8.8 4.7 Comparative Example 4 Comparative Example Compound c4 477 9.2 10.0 Comparative Example 5 Comparative Example Compound c5 476 9.4 23.4 Comparative Example 6 Comparative Example Compound c6 426 0.9 9.8 Comparative Example 7 Comparative Example Compound c7 448 5.7 1.9 Comparative Example 8 Comparative Example Compound c8 424 0.2 0.2 Comparative Example 9 Comparative Example Compound c9 459 10.8 2.4

Referring to the results of Table 1, it can be seen that Examples 1 to 4 have improved luminous efficiency and device lifetime compared to Comparative Examples 1 to 9. More specifically, Examples 1 to 4 emit light of a similar wavelength from each of Comparative Examples 1 to 4 including a dopant material having a similar structure, while improving luminous efficiency and device lifetime. In addition, compared to Comparative Examples 5 to 8 including a dopant material including an azacillin group and a carbazole group, the luminous efficiency and device lifetime were improved, and Comparative Example 9 including a dopant material in which an alkyl group was substituted for a germine Compared to , the luminous efficiency and life of the device were improved.

The example compounds included in Examples 1 to 4 include an azagermine group including heavy atom Ge as an electron donor. Therefore, due to heavy atoms included in the electron donor, spin orbital interaction (Spin Orbit Coupling) is increased, and singlet-triplet intersystem crossing may be promoted. Therefore, organic electroluminescent devices using this as a dopant material can efficiently perform thermally activated delayed fluorescence (TADF) without loss of energy of triplet excitons, so that high efficiency and long lifespan of organic electroluminescent devices can be achieved.

Comparative Example Compound c1 included in Comparative Example 1 has a structure similar to Example Compound 11, but contains acridine, not azazermine, as an electron donor. Accordingly, since the heavy atom effect by Ge cannot be implemented, Comparative Example 1 has lower luminous efficiency and device lifetime than Example 1.

Comparative Example Compound c2 included in Comparative Example 2, Comparative Example Compound c5 included in Comparative Example 5, and Comparative Example Compound c7 included in Comparative Example 7 are similar in structure to Example Compound 25, but each uses azazermine as an electron donor. but not acridine, azacillin, carbazole, and the like. Accordingly, since the heavy atom effect by Ge cannot be implemented, Comparative Examples 2, 5, and 7 have lower luminous efficiency and device lifetime than Example 2.

Comparative Example Compound c3 included in Comparative Example 3 has a structure similar to Example Compound 39, but contains acridine, not azazermine, as an electron donor. Accordingly, since the heavy atom effect by Ge cannot be implemented, Comparative Example 3 has lower luminous efficiency and device lifetime than Example 3.

Comparative Example Compound c4 included in Comparative Example 4, Comparative Example Compound c6 included in Comparative Example 6, and Comparative Example Compound c8 included in Comparative Example 8 are similar in structure to Example Compound 49, but each contains azazermine as an electron donor. but not acridine, azacillin, and carbazole, and the like. Accordingly, since the heavy atom effect by Ge cannot be implemented, Comparative Examples 4, 6, and 8 have lower luminous efficiency and device lifetime than Example 4.

Comparative Example Compound c9 included in Comparative Example 9 includes azazermine as an electron donor, but the substituent substituted for Ge is an alkyl group, not an aryl group. Accordingly, the stability of the azazermin group is reduced, and the luminous efficiency and device lifetime of Comparative Example 9 are lower than those of Example.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art can implement the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

10: organic electroluminescent element EL1: first electrode
HTR: hole transport region EML: light emitting layer
ETR: electron transport region EL2: second electrode
HTL: hole transport layer HTL1: first hole transport layer
HTL2: second hole transport layer

Claims (19)

A polycyclic compound represented by Formula 1 below:
[Formula 1]

In Formula 1,
Ar ₁ and Ar ₂ are each independently a substituted or unsubstituted phenyl group;
R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group, or may be bonded to an adjacent group to form a ring,
n ₁ and n ₂ are each independently an integer of 0 or more and 4 or less;
X ₁ is represented by any one of Formulas 2-3 to 2-5 and Formula 2-7 below.
[Formula 2-3]

[Formula 2-4]

[Formula 2-5]

[Formula 2-7]

In Formulas 2-3 to 2-5 and Formula 2-7,
W ₁ to W ₅ are each independently N or CR ₅ , and at least one of W ₁ to W ₅ is N;
L ₃ to L ₅ , and L ₇ are each independently a substituted or unsubstituted phenylene group;
Ar ₃ to Ar ₅ , and Ar ₇ are each independently a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and a substituted Alternatively, it may be an unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms, or bonded to an adjacent group to form a ring. According to claim 1,
The polycyclic compound represented by Formula 1 is a polycyclic compound represented by Formula 3 below:
[Formula 3]

In Formula 3,
X ₂ is represented by any one of Formulas 2-3 to 2-5 and Formula 2-7;
Ar ₁₁ and Ar ₁₂ are each independently a substituted or unsubstituted phenyl group,
R ₆ and R ₇ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group, or may be bonded to an adjacent group to form a ring,
n ₃ and n ₄ are each independently an integer of 0 or more and 4 or less. According to claim 2,
A polycyclic compound wherein L ₃ to L ₅ and L ₇ are substituted or unsubstituted phenylene groups. According to claim 2,
The polycyclic compound represented by Formula 3 is a polycyclic compound represented by Formula 4 below:
[Formula 4]

In Formula 4,
n ₅ is an integer from 1 to 4;
When n ₅ is 1,
X ₃ is a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfonyl group, or a phenyl group substituted with a substituent represented by Formula 5-2 below;
When n ₅ is an integer from 2 to 4,
X ₃ is a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfonyl group, or a phenylene group substituted with a substituent represented by Formula 5-2 below;
Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined in claim 2.
[Formula 5-2]

In Formula 5-2,
W ₆ to W ₁₀ are each independently N or CR ₁₀ , and at least one of W ₆ to W ₁₀ is N;
R ₁₀ is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted or unsubstituted nitro group , A substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted A sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for ring formation, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for ring formation. . According to claim 2,
The polycyclic compound represented by Formula 3 is a polycyclic compound represented by Formula 6 below:
[Formula 6]

In Formula 6,
L ₉ is a substituted or unsubstituted divalent carbonyl group, a substituted or unsubstituted divalent boron group, a substituted or unsubstituted divalent sulfonyl group, a substituted or unsubstituted unsubstituted pyridylene group, a substituted or unsubstituted divalent sulfonyl group, or a substituted or unsubstituted divalent boron group. A divalent diazinyl group (diazinyl), or a substituted or unsubstituted divalent triazinyl group (triazinyl),
Ar ₁₄ and Ar ₁₅ are each independently a substituted or unsubstituted phenyl group;
R ₁₁ to R ₁₄ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group, or may be bonded to an adjacent group to form a ring,
n ₆ to n ₉ are each independently an integer of 0 to 4;
Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined in claim 2. delete According to claim 1,
X ₁ is a polycyclic compound represented by any one of Formulas 2-3-1 to 2-3-3:
[Formula 2-3-1]

[Formula 2-3-2]

[Formula 2-3-3]

In Formulas 2-3-1 to 2-3-3,
n ₁₀ is an integer from 0 to 4;
n ₁₁ is an integer from 0 to 3;
n ₁₂ is an integer from 0 to 2;
L ₃ and R ₅ are the same as defined in claim 1. According to claim 1,
Wherein R ₁ and R ₂ are each independently a hydrogen atom, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group. According to claim 1,
The polycyclic compound represented by Formula 1 is any one selected from compounds represented by Compound Group 1 below:
[Compound group 1]

. delete delete a first electrode;
a hole transport region disposed on the first electrode;
a light emitting layer disposed on the hole transport region;
an electron transport region disposed on the light emitting layer; and
A second electrode disposed on the electron transport region;
The first electrode and the second electrode are each independently Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF/Ca, LiF/Al, Mo, Any one selected from the group consisting of Ti, In, Zn, and Sn, two or more compounds selected from these, a mixture of two or more selected from these, or one or more oxides selected from these,
The light emitting layer
An organic electroluminescent device comprising a polycyclic compound represented by Formula 1 below:
[Formula 1]

In Formula 1,
Ar ₁ and Ar ₂ are each independently a substituted or unsubstituted phenyl group;
R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group, or may be bonded to an adjacent group to form a ring,
n ₁ and n ₂ are each independently an integer of 0 or more and 4 or less;
X ₁ is represented by any one of Formulas 2-3 to 2-5 and Formula 2-7 below.
[Formula 2-3]

[Formula 2-4]

[Formula 2-5]

[Formula 2-7]

In Formulas 2-3 to 2-5 and Formula 2-7,
W ₁ to W ₅ are each independently N or CR ₅ , and at least one of W ₁ to W ₅ is N;
L ₃ to L ₅ , and L ₇ are each independently a substituted or unsubstituted phenylene group;
Ar ₃ to Ar ₅ , and Ar ₇ are each independently a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and a substituted Alternatively, it may be an unsubstituted aryl group having 6 or more and 30 or less ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 or more and 30 or less ring carbon atoms, or bonded to an adjacent group to form a ring. According to claim 12,
The light emitting layer
comprising a host and a dopant;
The dopant is
An organic electroluminescent device comprising a polycyclic compound represented by Chemical Formula 1. According to claim 12,
The polycyclic compound represented by Formula 1 is
An organic electroluminescent device having an energy difference (ΔE _ST ) between the lowest singlet energy level (S ₁ ) and the lowest triplet energy level (T ₁ ) of 0.2 eV or less. According to claim 12,
The polycyclic compound represented by Formula 1 is an organic electroluminescent device represented by Formula 3 below:
[Formula 3]

In Formula 3,
X ₂ is represented by any one of Formulas 2-3 to 2-5 and Formula 2-7;
Ar ₁₁ and Ar ₁₂ are each independently a substituted or unsubstituted phenyl group,
R ₆ and R ₇ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted group. Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group, or may be bonded to an adjacent group to form a ring,
n ₃ and n ₄ are each independently an integer of 0 or more and 4 or less. According to claim 15,
Wherein L ₃ to L ₅ and L ₇ are substituted or unsubstituted phenylene groups. According to claim 15,
The polycyclic compound represented by Formula 3 is an organic electroluminescent device represented by Formula 4 below:
[Formula 4]

In Formula 4,
n ₅ is an integer from 1 to 4;
When n ₅ is 1,
X ₃ is a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfonyl group, or a phenyl group substituted with a substituent represented by Formula 5-2 below;
When n ₅ is an integer from 2 to 4,
X ₃ is a substituted or unsubstituted carbonyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted sulfonyl group, or a phenylene group substituted with a substituent represented by Formula 5-2 below;
Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined in claim 2.
[Formula 5-2]

In Formula 5-2,
W ₆ to W ₁₀ are each independently N or CR ₁₀ , and at least one of W ₆ to W ₁₀ is N;
R ₁₀ is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted or unsubstituted nitro group , A substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, a substituted or unsubstituted sulfinyl group, a substituted or unsubstituted A sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for ring formation, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms for ring formation. . According to claim 15,
The polycyclic compound represented by Formula 3 is an organic electroluminescent device represented by Formula 6 below:
[Formula 6]

In Formula 6,
L ₉ is a substituted or unsubstituted divalent carbonyl group, a substituted or unsubstituted divalent boron group, a substituted or unsubstituted divalent sulfonyl group, a substituted or unsubstituted unsubstituted pyridylene group, a substituted or unsubstituted divalent sulfonyl group, or a substituted or unsubstituted divalent boron group. A divalent diazinyl group (diazinyl), or a substituted or unsubstituted divalent triazinyl group (triazinyl),
Ar ₁₄ and Ar ₁₅ are each independently a substituted or unsubstituted phenyl group;
R ₁₁ to R ₁₄ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted boron group, a substituted or unsubstituted amino group, a substituted or unsubstituted cyano group, a substituted or unsubstituted carbonyl group, or a substituted Or an unsubstituted nitro group, a substituted or unsubstituted oxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted phosphine sulfide group, or a substituted or unsubstituted sulfinyl group. , a substituted or unsubstituted sulfonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms for forming a ring, or a substituted or unsubstituted aryl group having 2 to 30 carbon atoms for forming a ring It is the following heteroaryl group, or may be bonded to an adjacent group to form a ring,
n ₆ to n ₉ are each independently an integer of 0 to 4;
Ar ₁₁ , Ar ₁₂ , R ₆ , R ₇ , n ₃ , and n ₄ are the same as defined in claim 2. According to claim 12,
An organic electroluminescent device wherein the polycyclic compound represented by Formula 1 is any one selected from compounds represented by compound group 1 below:
[Compound group 1]

.

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